Meta-Analysis of the Mitigation Effects of Supplementation With Calcium Salts of Unsaturated Fatty Acids on Enteric Methane Emissions in Beef Cattle and Its Impact on Meat Quality.

This study evaluated the effects of calcium salts of unsaturated fatty acids (CSUFAs) on enteric methane (CH4) emissions and meat quality in beef cattle by integrating data from trials on beef cattle of different production stages, sexes, and breeds. Specifically, a meta-analysis of four studies including 44 animals (22 with CSUFAs and 22 as a control) was performed to assess CH4-related outcomes. Daily CH4 emissions in all experiments were estimated by multiplying the breath CH4:CO2 concentration ratio by estimated CO2 emissions. CSUFA supplementation tended to reduce CH4 emissions per unit of total digestible nutrient intake (CH4/TDNI; mean difference = -2.2 L/kg, p = 0.077), corresponding to a reduction of 5.6%. Meanwhile, no significant differences were observed for the CH4:CO2 ratio, daily CH4 emissions, or CH4 per unit of dry matter intake. Physicochemical analysis of meat from 16 animals revealed no adverse effects of CSUFA supplementation on meat quality. Descriptive sensory evaluation indicated improved juiciness, fat flavor richness, and other sensory attributes upon CSUFA supplementation (p < 0.05). These findings suggest that CSUFAs can reduce enteric CH4 emissions relative to dietary energy density while maintaining meat quality, supporting their use as a practical strategy for mitigating CH4 emissions from beef cattle.